For the first time since an Oval Office taping system was removed by Richard Nixon's chief of staff 43 years ago, a president has hinted that White House conversations might again be secretly recorded. If so, Donald Trump is following a problematic precedent.

For the first time since an Oval Office taping system was removed by Richard Nixon's chief of staff 43 years ago, a president has hinted that White House conversations might again be secretly recorded. If so, Donald Trump is following a problematic precedent.

While several presidents secretly recorded conversations without problems, the practice is most associated with Nixon. His recordings became prime evidence during the Watergate investigation that ultimately led to his resignation. Sooner or later, recordings are likely to become public.

"The lesson for presidents since Nixon was, do not tape your Oval Office conversations," said Timothy Naftali, a professor at New York University and the first federal director of the Richard Nixon Presidential Library and Museum in Yorba Linda, California. "It can only get you in trouble."

Trump tweeted last Friday that former FBI director James Comey "better hope that there are no 'tapes' of our conversations before he starts leaking to the press".

The extraordinary, if ambiguous, tweet came three days after Trump fired Comey, who was overseeing the bureau's investigation into Russian meddling in the presidential election and whether anyone in Trump's campaign was involved.

Trump has rejected the probe as "fake news", and claimed Comey assured him at a dinner and in two phone calls that he was not under investigation. Comey has not spoken publicly since he was fired, but an associate said Trump's claims are puzzling, adding that Trump sought a loyalty pledge from Comey, which he declined to give, during the White House dinner on January 27.

That and similar reports apparently led to Trump's tweet.

White House spokesman Sean Spicer did not comment when asked whether Trump recorded Comey, or if recording equipment exists in the Oval Office.

Under a post-Watergate law, the Presidential Records Act, recordings made by presidents belong to the people and can eventually be made public. Destroying them would be a crime. The top Democrat on the House Intelligence Committee, Adam Schiff, has already seized on the tweet and asked that Trump give Congress any recordings of conversations with Comey.

Federal law allows the secret recording of conversations so long at least one person in the conversation is aware of the recording. Trump's home state New York has a similar law. In Florida, where Trump has his Mar-a-Lago estate, both parties must consent to any recording.

There is a rich history of secret presidential recordings since Franklin D Roosevelt. Tapes of John F Kennedy in the Oval Office helped cement his reputation as a strong leader during multiple crises. Lyndon Johnson also recorded conversations.

But Nixon's recordings are the most famous. His dismissal of special prosecutor Archibald Cox, who subpoenaed the White House for the president's tapes, marked the beginning of the end of his presidency. Nixon chief of staff Alexander Haig had the recording system - complete with five listening devices in the president's desk in the Oval Office - removed on July 16, 1973, but it was already too late. Nixon resigned a year later.

Trump "is emulating some of the worst aspects of Richard Nixon and for those of us watching from the outside, we have to ask why", said Naftali, adding: "Why would he bring up the taping system? Why? I'm not saying he has one, but why would any president after Nixon even jest about a taping system?"

Trump worried about recorded conversations - and recording his own conversations - well before he got into politics, according to former Trump Organisation executives.

After Trump tweeted in March that President Barack Obama had ordered a wiretap on his phones in Trump Tower, three ex-employees told The Associated Press that, as a businessman, Trump not only worried about possible listening devices in his phones and office but had also occasionally taped his own phone conversations. Trump once denied doing so.

And at his New York office during the campaign, workers believed Trump had a system set up to record phone calls.

"I would note that New York is a one-party consent state and President Trump has always abided by the law," said Sam Nunberg, a former campaign aide, referring to the law that permits taping conversations without the knowledge of one of the participants.

For a White House accustomed to bouts of chaos, Trump's handling of Comey's firing could have serious and long-lasting implications.

Already Trump's decision appears to have emboldened the Senate intelligence committee investigating into Russia's election interference and the president's associates, with lawmakers announcing a subpoena for former national security adviser Michael Flynn. Comey's allies also quickly made clear they would defend him against attacks from Trump, including disputing the president's assertion that Comey told Trump he was not personally under investigation.

Several people close to the president say his reliance on a small cadre of advisers as he mulled firing Comey reflects his broader distrust of many of his own staffers. He leans heavily on daughter Ivanka and son-in-law Jared Kushner, as well as Hope Hicks, his trusted campaign spokeswoman, and Keith Schiller, his long-time bodyguard. Schiller was among those Trump consulted about Comey, and was tapped by the president to deliver a letter informing the director of his firing.

Trump confidants said Steve Bannon has been marginalised on major decisions, including Comey's firing, after clashing with Kushner. And while Trump praised chief of staff Reince Priebus after the House passed a healthcare bill last week, associates said the president has continued to raise occasional questions about Priebus' leadership in the West Wing.

Trump spent most of last week out of sight, a marked change from a typically jam-packed schedule that often includes multiple on-camera events each day. Even when aides moved ahead on an executive order creating a voter fraud commission - a presidential pet project that some advisers thought they had successfully shelved - Trump signed the directive in private.

More than a lack of momentum on major policy goals, Trump is said to be seething over the flood of leaks pouring out of the White House and into news reports. He has viewed even senior advisers suspiciously, including Bannon and Priebus, when stories about White House drama land in the press.

A dozen White House officials and others close to Trump detailed the president's decision-making and his mood on the condition of anonymity in order to discuss private conversations and deliberations.

After Trump decided to fire Comey, he was told by aides that Democrats would likely react positively to the news given the role many believe Comey played in Hillary Clinton's defeat last year. When the opposite occurred, Trump grew incensed - both at Democrats and his own communications staff for not quickly lining up more Republicans to defend him on television.

Much of Trump's ire has been focused on the communications team, all of whom were caught off guard by Comey's ouster. He increasingly sees himself as the White House's only effective spokesperson, according to multiple people who have spoken to him. By the end of last week, Trump was musing about cutting back on the White House's televised press briefings.

Two White House officials said some of Trump's frustration centres on what he views as unfair coverage of his decisions and overly harsh criticism of press secretary Sean Spicer, as well as deputy press secretary Sarah Sanders, who led much of the response to Comey's firing. Aides said Trump does not believe his team gave contradictory stories about his decision to fire Comey, despite the fact that the White House's explanation changed dramatically over a 48-hour period. The White House initially said Trump was compelled to fire Comey by a critical memo from the deputy attorney general on the director's handling of last year's investigation into Clinton's email. Aides later said the president had been considering firing Comey for months, and Trump said he would have made the decision regardless of the Justice Department recommendation.

"The challenge they have is that the president sometimes moves so rapidly that they don't get a team around that gets it organised," said Newt Gingrich, the former House speaker and Trump ally.

"He's a little bit like a quarterback that gets ahead of his offensive line."

But the fallout from Comey's sacking left the White House reeling once again. Trump's visible anger and erratic tweets prompted a reporter to ask Spicer last Friday if the president was "out of control".